Among agrochemical formulations, an emulsifiable concentrate, a wattable powder, a suspension concentrate and the like are known as a formulation which is sprayed after being diluted with water. Among them, a water-soluble liquid formulation (SL liquid formulation) is preferably used from the viewpoint of easy handling and the like. Furthermore, neonicotinoid-based (another name is chloronicotinyl) compounds such as imidacloprid and acetamiprid are known to have excellent insecticidal activity. For this reason, various water-soluble liquid formulations containing the neonicotinoid-based compound as an agrochemical active ingredient have been proposed.
For example, a concentrated water-soluble solution containing imidacloprid, a natural emulsifier based on alkylaryl polyglycol ether, sodium diisooctyl sulfosuccinate, dimethyl sulfoxide and isopropanol (PTL 1, Example 3); a concentrated water-soluble solution containing imidacloprid, sodium diisooctyl sulfosuccinate, dimethyl sulfoxide, triethanolamine salts of alkylbenzene sulfonic acid, sodium salt of alkylbenzene sulfonic acid, condensation product of oleic acid and diethanol amine, and polyethylene glycol (PTL 1, Example 4); an insecticide composition formed of a homogeneous solution which is formed by dissolving acetamiprid in a mixed solvent containing γ-butyrolactone and dimethyl sulfoxide, and by dissolving polyoxyethylene-hardened castor oil or a ethylene oxide propylene oxide block copolymer as a surfactant (PTL 2); an agrochemical composition formed of acetamiprid, polyoxyalkylene alkyl ether, γ-butyrolactone and dipropylene glycol (PTL 3); and a liquid composition for treating a plant-propagating material formed of thiamethoxam, polydimethylsilane, copolymer butanol PO/EO and sodium naphthalenesulfonate (PTL 5) have been proposed.